By Kathy Van Mullekom
Daily Press (Newport News, Va.)
Carole and Wiley Waters are longtime rose growers who fear roses are unfairly getting a bad reputation.
“Roses have gotten a bad rap because of Rose Rosette Disease, but we have seen very little to none of it,” says Wiley Waters of Yorktown, Va.
“We hate to see people give up on growing roses.”
Rose Rosette Disease has been spreading through much of the wild rose population in the Midwestern, southern and eastern United States for years, according to research by Chuan Hong, a plant pathologist with Virginia Tech in Blacksburg, Va. Recently, it’s been confirmed in cultivated roses — Knock Out, Drift and Flower Carpet roses, to name a few popular types — in Virginia and many other states.
Even so, Wiley thinks roses still belong in the home garden.
Now a retired educator, Wiley Waters grew up with roses, tending to neighbors’ plants at 25 cents per hour, and helping his father with family flowers. Members of the Virginia Peninsula Rose Society, the couple cared for the rose garden at Huntington Park in Newport News, Va., for 10 years, and now have their own rose-care business — Waters Rose Care Service — that helps homeowners with rose needs. Their own small yard is home to 82 roses — hybrid teas, grandifloras, floribundas, shrubs, climbers, miniatures and tree forms.
His favorite among all those is the hybrid tea Mister Lincoln, which has been around since 1965.
“The classic red blooms have an intense damask fragrance on strong long stems,” he says.
“When people see a rose, they automatically expect it to smell good, and this number one rose never disappoints that expectation.”
Good sanitation practices in the garden help prevent roses from most major problems, he says. Pick up fallen leaves and petals that can help transmit disease and insects, and keep the plants healthy with proper nutrition. Remove faded, spent blooms weekly; stop deadheading in early October to allow plants to harden up for winter. Water 1-2 inches weekly when there is no rainfall, preferably with drip irrigation that keeps leaves dry and freer of foliage disease.
For their roses, the couple uses a blend of topsoil, compost and sand they purchased from a local hardwood mulch supplier. Fertilizers they recommend include: Miracle Gro for roses; Peters 20-20-20; slow-release, all-purpose Sta-Green; Osmocote in 3- or 6-month formula; or Bayer All in One fertilizer, insect and disease control.
In winter, they suggest rose growers clean and mulch beds, prune tall canes no more than 4 feet tall to protect against wind damage; when plants are dormant, spray plants and beds with lime sulfur. Spray for bad insects such as aphids and thrips, as needed, and use preventive sprays for things like black spot and powdery mildew.
Rose Rosette Disease, first documented in 1941, is traced to the multiflora rose, which came from Japan in 1866 as a common rootstock for ornamental roses. Unfortunately, it was found that multiflora roses are bad because a single plant can produce a million or more viable seeds per plant; over time, the roses have become known as invasive weeds with enormous disease problems. Today, new roses like Knock Out and Drift roses are grown on their own rootstock.
Small mites spread Rose Rosette Disease, and no effective controls are available for existing infected roses. Disease characteristics include witches’ broom growth, or clustering of small branches, as well as reddening, distorted, stunted and elongated leaves. Infected plants should be destroyed, according to most experts.
Mark Windham, a professor in the entomology and plant pathology department at the University of Tennessee, has done extensive research on Rose Rosette Disease, which he heard about in the early 1990s and now studies through a grant from the American Rose Society. He’s also rose adviser for the Beall Family Rose Garden at the University Tennessee Gardens in Knoxville.
“We live with Rose Rosette Disease every day,” he says of the garden’s 200 plants.
“We are constantly vigilant for symptomatic plants. Someone inspects each plant at least five days a week, and any rose that becomes symptomatic is immediately removed and destroyed. Roses next to the diseased rose are tagged and monitored the rest of the season. We lose four to eight plants each year to Rose Rosette Disease.”
Even though the short-term future for roses looks scary, Windham is confident the rose industry and researchers will eventually identify sources for breeding resistance into new cultivars. There are no known controls for the virus, he says.
“Horticultural oils and Neem oil might help, but there is no data,” he says.
“The key is constant vigilance for symptoms of the disease and not trying to ‘save’ any rose that is symptomatic.”